Cell Reproductin

Associate Program Material

Cell Energy Worksheet

Answer the following questions:

  Cellular respiration:

    • What is cellular respiration and what are its three stages?
      A chemical process called cellular respiration harvests energy that is stored in sugars and other organic molecules. Cellular respiration is a metabolic process in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then produce waste products. Cellular respiration uses O2 to help convert energy extracted from organic fuel to another source of chemical energy, called ATP. Cells expend ATP for almost all their work. In both plants and animals, the production of ATP during cellular respiration occurs mainly in the organelles called mitochondria. The three stages of cellular respiration are:
    1. Glycolysis means “splitting of sugar.”
    2. The Citric Acid Cycle
    3. Electron Transport

    • What is the role of glycolysis? Include the reactants and the products. Where does it occur?

  Glycolysis means “splitting of sugar.”
  1. During glycolysis, a six-carbon glucose molecule is broken in half, forming two three-carbon molecules. The initial split requires an energy investment of two ATP molecules per glucose.
  2. The three-carbon molecules then donate high-energy electrons to NAD_, the electron carrier, forming NADH.
  3. In addition to NADH, glycolysis also makes four ATP molecules directly when enzymes transfer phosphate groups from fuel molecules to ADP. Glycolysis thus produces a net of two molecules of ATP per molecule of glucose.

    • What is the role of the citric acid cycle? Include the reactants and the products. Where does it occur?

      Pyruvic acid, the fuel that remains after glycolysis, is not quite ready for the citric acid cycle. First, pyruvic acid loses a carbon as CO2. This is the first of this waste product that shows up   in the breakdown of...